如何对元素类型为字符串别名而不是字符串本身的Go切片进行排序？

Question

type MyObject string
var objects []MyObject

I want to sort these objects. The standard library has sort.Strings, but that requires an instance of []string instead of []MyObject.

My current solution is to implement sort.Interface (as shown below) and use sort.Sort, but I'd like to get rid of that boilerplate code. Is there a nicer way?

type MyObjects []MyObject

func (objs MyObjects) Len() int {
    return len(objs)
}

func (objs MyObjects) Less(i, j int) bool {
    return strings.Compare(string(objs[i]), string(objs[j])) < 0
}

func (objs MyObjects) Swap(i, j int) {
    o := objs[i]
    objs[i] = objs[j]
    objs[j] = o
}

Answer 1

No. Since Go doesn't allow the implicit conversion of types within slices (there is also no covariance with interfaces), you need to supply the appropriate methods for your type.

type MyObjects []MyObject

func (p MyObjects) Len() int           { return len(p) }
func (p MyObjects) Swap(i, j int)      { p[i], p[j] = p[j], p[i] }
func (p MyObjects) Less(i, j int) bool { return p[i] < p[j] }

If you really want to do this, you could use unsafe (but please don't). I doubt those 3 extra lines of safe code are going to make that big a difference for you.

http://play.golang.org/p/d6ciFjjr2c

objects := []MyObject{"one", "two", "three", "four"}
sort.Strings(*(*[]string)(unsafe.Pointer(&objects)))